You must specify the service channel. The device's Address won't have a service channel as thisis how it differentiate between the services. Compare with how FTP works with TCP/IP and a port number. The address is the computer, the port is the specific FTP service. It's the same thing here, the Address just points out the correct device, then you need to specify the service channel to determine which service you wish to connect too.
When you run the service discovery you can see the channel number, it's the number after the ':'